U.S. Pat. No. 3,836,670 relates to, inter alia, 5,6,7,8,9,10-hexahydro-3-substituted-5-substituted-5,9-methanobenzocyclooc ten-11-amines, and 5,6,7,8,9,10,11,12-octahydro-3-substituted-5-substituted-5,11-methanobenzo cyclodecen-13-amines. This application relates to compounds having a similar parent ring structure, but which have alkyl substituents introduced in a spiro arrangement on the macrocyclic ring. These substituents are located in a position whereby they may be expected to have a significant influence on the relative spatial position of the carbocyclic ring systems and the amino substituent relative to the known non-psiro substituted compounds.